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Subject: Re: [PATCH] MAXCPU alterable in kernel config - needs testers
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David Xu wrote:

> I think MAXCPU should not be great than 32, since we currently define
> cpumask_t as an integer which now should be changed to a bitmap and
> a group of operations like we did for sigset_t.

Maybe there should be an option "MANYCPUS" that wraps current calls that
manipulate this int value into calls that operate on a bitmap, so
there's no speed loss in machines with low number of CPUs. Also, why not
use a 64-bit int on 64-bit platforms for the mask? This will cover at
least Niagara 2 by default.